In an effort to improve indoor lighting conditions and the aesthetic appeal of enclosed spaces, architects and builders have begun to construct buildings using an increasing large amount of glazing materials and systems, such as windows, skylights, and transparent or translucent walls and roofs. While the use of such glazing materials can dramatically improve the quality of indoor lighting, buildings incorporating relatively large amounts of such glazing materials often are poorly insulated. More specifically, the thermal transmission of conventional glazing materials typically is significantly higher than the thermal transmission of conventional building materials or structures, such as framed roofs and walls. Therefore, the overall thermal transmission of a building incorporating relatively large amounts of such glazing materials typically is significantly higher than a similar structure using less of the same, and such buildings often experience relatively large amounts of heat flux across the glazing materials, which can dramatically increase the cost of maintaining the climate within the building at a level considered comfortable by the occupants. Accordingly, several attempts have been made to address the relatively poor (i.e., high) thermal transmission of conventional glazing materials and systems.
For example, glazing materials and systems, such as windows, have been developed which incorporate an air space between two vitreous (e.g., glass) or thermoplastic surfaces. One such popular glazing material is commonly referred to as a “multiwall panel.” These multiwall panels typically comprise two thermoplastic sheets and a plurality of supporting members disposed between the thermoplastic sheets. The thermoplastic sheets and the supporting members together define a plurality of chambers disposed between the thermoplastic sheets and the supporting members. Insofar as gases have lower thermal conductivities than solid materials, such as glass and thermoplastics, the gases within the chamber provide an insulating layer that serves to decrease and/or retard thermal transmission across the panel. While such multiwall panels do exhibit improved (i.e., lower) thermal transmission than conventional, single-pane glazing materials, condensation often forms within the chambers as the panels are exposed to differences in temperature and/or humidity across the major surfaces of the panel. The humid environment provided by such condensation can promote the growth of mold and mildew within the chambers of the panel. Furthermore, the structure of the multiwall panels often causes the panel to unevenly refract visible light, which can negatively impact the indoor lighting quality of a structure incorporating the panels as a glazing material.
Another glazing system that has been developed to provide an improved (i.e., lower) thermal transmission relative to conventional glazing materials and systems is commonly referred to as double-glazed U-profile or U-channel glass. These glazing systems typically comprise a pair of U-shaped glass elements disposed in such a way as to form a chamber between the two elements. While the gases contained within this channel can retard thermal transmission across the glazing system (i.e., between the two glass elements), the glazing system typically further comprises an insulating material disposed within the chamber formed between the two elements. The most commonly used insulating material is a rigid panel which consists of a plurality of acrylic (e.g., poly(methyl methacrylate)) capillaries covered by two glass fiber mats. The individual acrylic capillaries are arranged in a substantially parallel direction so that the panel resembles a honeycomb structure, the ends of which are covered by the glass fiber mats. These rigid insulation panels can often dramatically improve (i.e., lower) the thermal transmission of a glazing system incorporating the same.
However, the costs saved due to the improved thermal transmission of the glazing system can often be partially offset by the relatively high labor costs associated with the installation of such insulating panels. For instance, the insulating panels are extremely fragile and frequently break during the installation due to their relatively large dimensions (e.g., up to about 6 meters or more in length). The debris generated by such breakage (e.g., glass fibers) can create an environmental hazard for the workers installing the insulating panels and must be painstakingly removed. Furthermore, the insulating panels typically are adhered to one of the glass elements (e.g., the glass element facing the outside of the building) before the other glass element is installed. In such a configuration, the insulating panel impedes the drainage of condensation that forms on the glass element to which the panel is adhered. As noted above, the humid environment provided by such condensation can then promote the growth of mold and mildew within the chamber formed by the glass elements.
A need therefore exits for an insulated panel that is suitable for use as a glazing material and a glazing system comprising such an insulated panel, both of which address the foregoing and other problems associated with existing insulated glazing materials and systems. The invention provides such an insulated panel and glazing system. These and other advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.